A TGI Fridays operator in New Jersey has been fined $500,000 for a sneaky bait-and-switch scheme in which customers have been paying for top-shelf alcohol but getting shortchanged with cheaper alternatives, reports MSN Money.

Thanks to a raid called “Operation Swill,”100 investigators invaded 29 New Jersey bars — including 13 TGI Fridays. They found that eight of its restaurants were scamming their customers. The restaurants, managed under the Briad Group, “filled premium alcohol beverage bottles with cheaper alcohol in attempt to deceive customers while increasing profits,” the Manasquan Patch site said.

“This unlawful practice took advantage of consumers who were cheated out of what they thought they were purchasing,” Attorney General John J. Hoffman announced. “This fine should send a clear message to every bar and restaurant throughout New Jersey that customers should get what they pay for every time without exception.”

Under the settlement’s terms, the Briad Group agreed not to contest the charges. A monitor appointed by New Jersey state will supervise the restaurants to ensure the employees are complying with the law. If there are “no further violations during that period, the businesses will avoid five-day suspensions of their liquor licenses, the attorney general said,” according to MSN Money.

While the details of TGI Fridays’ specific deceptive tactics remain unclear, one unnamed New Jersey bar — caught by Operation Swill — has been allegedly using rubbing alcohol with caramel food coloring and disguising it as “scotch.” At another location, a bar is being accused of pouring scummy water into an empty bottle and calling it “liquor.”

The eight TGI Fridays that are in hot water for the sham are located West Orange, East Windsor, Marlboro, Old Bridge, Piscataway, Freehold, Hazlet and Linden.

The fine is comprised of $400,000 for the violations plus $100,000 to cover the cost of Operation Swill.